Anatomic renal artery branch microdissection to facilitate zero-ischemia partial nephrectomy

Background

Robot-assisted and laparoscopic partial nephrectomies (PNs) for medial tumors are technically challenging even with the hilum clamped and, until now, were impossible to perform with the hilum unclamped.

Objective

Evaluate whether targeted vascular microdissection (VMD) of renal artery branches allows zero-ischemia PN to be performed even for challenging medial tumors.

Design, setting, and participants

A prospective cohort evaluation of 44 patients with renal masses who underwent robot-assisted or laparoscopic zero-ischemia PN either with anatomic VMD (group 1; n = 22) or without anatomic VMD (group 2; n = 22) performed by a single surgeon from April 2010 to January 2011.

Intervention

Zero-ischemia PN with VMD incorporates four maneuvers: (1) preoperative computed tomographic reconstruction of renal arterial branch anatomy, (2) anatomic dissection of targeted, tumor-specific tertiary or higher-order renal arterial branches, (3) neurosurgical aneurysm microsurgical bulldog clamp(s) for superselective tumor devascularization, and (4) transient, controlled reduction of blood pressure, if necessary.

Measurements

Baseline, perioperative, and postoperative data were collected prospectively.

Results and limitations

Group 1 tumors were larger (4.3 vs 2.6 cm; p = 0.011), were more often hilar (41% vs 9%; p = 0.09), were medial (59% and 23%; p = 0.017), were closer to the hilum (1.46 vs 3.26 cm; p = 0.0002), and had a lower C index score (2.1 vs 3.9; p = 0.004) and higher RENAL nephrometry scores (7.7 vs 6.2; p = 0.013). Despite greater complexity, no group 1 tumor required hilar clamping, and perioperative outcomes were similar to those of group 2: operating room time (4.7 and 4.1 h), median blood loss (200 and 100 ml), surgical margins for cancer (all negative), major complications (0% and 9%), and minor complications (18% and 14%). The median serum creatinine level was similar 2 mo postoperatively (1.2 and 1.3 mg/dl). The study was limited by the relatively small sample size.

Conclusions

Anatomic targeted dissection and superselective control of tumor-specific renal arterial branches facilitate zero-ischemia PN. Even challenging medial and hilar tumors can be excised without hilar clamping. Global surgical renal ischemia has been eliminated for most patients undergoing PN at our institution.     

Impact of a multidisciplinary trauma team on the outcome of acute subdural haematoma

IntroductionTo review the outcome of patients with post-traumatic acute subdural haematoma (ASDH) before and after the establishment of a hospital trauma team at a designated trauma centre.MethodA retrospective analysis was conducted on 82 consecutive patients who underwent surgery for post-traumatic ASDH. The ‘PRE’ and ‘POST’ groups included patients admitted before and after the establishment of a hospital trauma team, respectively.Injury severity was assessed by the admission Glasgow coma score, imaging findings, and the revised trauma score. Clinical outcome measures were the hospital length of stay and the Glasgow outcome score (GOS) upon hospital discharge.ResultsThe overall mortality rate was 53.7%. No significant difference was found between the PRE and POST groups. The mean length of hospital stay was also comparable between the two groups. The functional status of those who survived acute hospital care was significantly better in the POST group. Good outcome (GOS of 4 or 5) was achieved in 66.7% of the survivors in the POST group, compared with 25.0% in the PRE group (p = 0.024).ConclusionPost-traumatic ASDH carried a poor prognosis. The mortality rate and hospital length of stay of patients were not found to be reduced after the establishment of a hospital trauma team. The latter, however, was associated with significantly better functional outcome amongst survivors. Although causality cannot be established due to the multitude of factors which may have affected patient outcome, our findings nonetheless provide further support for the introduction of a multidisciplinary hospital trauma team for the optimal care of trauma patients.     

Scale‐up of MSC under hypoxic conditions for allogeneic transplantation and enhancing bony regeneration in a rabbit calvarial defect model

To realize the therapeutic potential of mesenchymal stem cells (MSCs), we aimed to develop a method for isolating and expanding New Zealand rabbit MSCs in a great scale. Rabbit MSCs expanded under hypoxic and normoxic conditions were compared in terms of replication capacity, differentiation potential, and the capacity for allogeneic transplantation in a calvarial defect model. The cells from all tested rabbits were expanded more rapidly when plated at low‐density under hypoxic conditions compared to under normoxic conditions. Moreover, cells expanded under hypoxic conditions increased in the potential of osteoblastic, adipocytic, and chondrocytic differentiation. More importantly, radiographic analysis and micro‐CT measurement of bone volume revealed the hypoxic cells when transplanted in the calvarial defects of another rabbit increased in the ability to repair bone defect compared to the normoxic cells. Six weeks after allogeneic transplantation of hypoxic MSCs, histological analysis revealed a callus spanned the length of the defect, and several bone tissues spotted in the implant. At 12 weeks, new bone had formed throughout the implant. Using BrdU labeling to track the transplanted cells, the hypoxic cells were more detected in the newly formed bone compared to the normoxic cells. For defects treated with allogeneic MSCs, no adverse host response could be detected at any time‐point. In conclusion, we have developed a robust method for isolation and expansion of rabbit MSCs by combining low‐density with hypoxic culture, which can be applied for the design of clinical trials in allogeneic transplantation of MSCs for bone healing. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1213–1220, 2012     

Trimethylamine N‐oxide as a media supplement for cartilage tissue engineering

Supplements added to the culture media (e.g., growth factors and dexamethasone) have been successful in improving mechanical and biochemical properties of engineered cartilage towards native values. Trimethylamine N‐oxide (TMAO), a natural osmolyte found in shark cartilage, is thought to induce protein folding, and counteracts the destabilizing effect of the high concentrations of urea stored by sharks. The objective of this study was to investigate the use of TMAO as a media supplement for promoting growth of functional engineered cartilage in culture. In the first study, TMAO was added to the culture media for the first 14 days in culture and concentrations of 0–200 mM were evaluated. In the second study, TMAO was supplemented to the culture media following chondroitinase ABC digestion, which has been previously shown to mediate an increased collagen content in engineered cartilage. A dose‐dependent response was observed with improved mechanical and biochemical properties for engineered constructs cultured with TMAO at concentrations of 5–100 mM. The Young's modulus of digested constructs cultured in TMAO was 2× greater than digested constructs cultured in the control medium and recovered to undigested control levels by day 42. In conclusion, these initial studies with TMAO as a media supplement show promise for improving the compressive mechanical properties, increasing extracellular matrix production, and increasing the recovery time following chABC digestion. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1898–1905, 2012     

Laparoscopic live donor nephrectomy: Current practice and results of renal transplantation

Objective: In 2009, 1659 patients with end‐stage renal failure in Hong Kong were waiting for a renal transplant. The overall number of renal transplants carried out locally remains low, with an even lower number being live donor donations. Yet, live donor kidney transplantation yields results that are consistently superior to those of deceased donor kidney transplantation, and laparoscopic donor nephrectomy (LDN) is increasingly accepted worldwide as a safe and preferred surgical option. We aim to evaluate the outcome of LDN in our setting, and to compare with that of deceased donors in this retrospective review. Patients and Methods: A total of 12 patients received LDN over the study period of 2006–2009. Standard left transperitoneal LDN was carried out. Grafts including three with double vessels were prepared using the bench technique. The postoperative outcomes up to 1 year for both the donors and the recipients were studied. Contemporary results for the 47 deceased donor kidneys were studied and compared. Results: All donors had an eventful recovery. The operating time was 225.0 ± 67.4 min. The hospital stay was 5.6 ± 2.3 days. The recipient outcomes including hospital stay and creatinine levels at discharge and 1 year were 11 days, 121 umol/L and 116 umol/L, respectively. Specifically, no ureteric stricture or graft loss was noted at the 1‐year follow up. Recipient complications included haematoma (1 patient), renal artery stenosis (1 patient) and redo of vascular anastomosis (1 patient). In contrast, the deceased donor graft recipients had a hospital stay of 11 days, and creatinine levels of 205 umol/L on discharge and 205 umol/L at 1 year, respectively. The delayed graft function rates for the live donor and deceased donors group were 0% and 14.9%, whereas the 1‐year graft survival rates were 100% and 87.2% respectively. Conclusion: The results showed that the donor morbidity rate was low, as reflected by the short hospital stay. Also, the overall parameters of recipients were good. In particular, no ureteric stricture was noted, and graft survival was 100% at 1 year. Living donor kidney transplant program using the laparoscopic technique is a viable option to improve the pool of kidneys for transplantation.     

Quantitative assessment of impaired postevacuation brain re-expansion in bilateral chronic subdural haematoma: Possible mechanism of the higher recurrence rate

IntroductionRecurrence of chronic subdural haematoma (CSDH) occurs in up to 30% of patients. The rate of recurrence is higher in bilateral versus unilateral CSDH and the reason for this has not been fully elucidated. There are few quantitative studies of temporal changes in brain re-expansion after haematoma evacuation. The aim of this study is to use a simple volumetric image analysis method to quantify temporal changes of postoperative brain re-expansion in unilateral and bilateral CSDH.MethodsWe reviewed computed tomography (CT) scans of 20 consecutive patients (16 men, 4 women; median age, 73.5 years) with CSDH (unilateral, n = 10; bilateral, n = 10) who underwent surgery (burr hole drainage on one or both sides) at our institutions during the period from June 2006 to August 2008. Haematoma volume was quantified preoperatively and on postoperative days 14 and 30 by computer-based image analysis (PACS Web 1000 System) of CT scans. We then calculated the brain re-expansion rate (BRR) for postoperative days 14 and 30.ResultsHaematoma volume remained significantly higher (p < 0.001) in bilateral versus unilateral CSDHs at both postoperative time points, and the BRR was significantly greater (p < 0.001) in unilateral versus bilateral CSDH at both time points.ConclusionResults of this quantitative analysis provide definitive evidence for a poor BRR in bilateral compared to unilateral CSDH. This impairment may result in shifting of the brain and shearing of blood vessels, resulting in a higher recurrence rate.     

Focal cryotherapy for clinically unilateral, low-intermediate risk prostate cancer in 73 men with a median follow-up of 3.7 years

Background

Evolution of cryotherapy for prostate cancer is likely to result in parenchyma-sparing modifications adjacent to the urethra and neurovascular bundle. Results of initial series of focal therapy to minimize cryosurgery-related morbidity without compromising oncologic control have been encouraging, but limited in short-term outcomes.

Objective

To retrospectively report (1) median 3.7-yr follow-up experience of primary focal cryotherapy for clinically unilateral prostate cancer with oncologic and functional outcomes, and (2) matched-pair analysis with contemporaneous patients undergoing radical prostatectomy (RP).

Design, setting, and participants

Over 8.5 yr (September 2002 to March 2011), focal cryoablation (defined as ablation of one lobe) was performed in 73 carefully selected patients with biopsy-proven, clinically unilateral, low-intermediate risk prostate cancer. All patients underwent transrectal ultrasound (TRUS) and Doppler-guided sextant and targeted biopsies at entry.

Outcome measurements and statistical analysis

Post-therapy follow-up included measuring prostate-specific antigen (PSA) level every 3–6 mo; TRUS biopsies at 6–12 mo and yearly, as indicated; and validated symptom questionnaires. Matched-pair analysis compared oncologic outcomes of focal cryotherapy and RP (matched for age, PSA, clinical stage, and biopsy Gleason score).

Results and limitations

Complete follow-up was available in 70 patients (median follow-up: 3.7 yr; range: 1–8.5 yr). No patient died or developed metastases. Precryotherapy mean PSA was 5.9 ng/ml and Gleason score was 6 (n = 30) or 7 (n = 43). Postcryotherapy mean PSA was 1.6 ng/ml (70% reduction compared to precryotherapy; p < 0.001). Of 48 patients undergoing postcryotherapy biopsy, 36 (75%) had negative biopsies; positive biopsy for cancer (n = 12) occurred in the untreated contralateral (n = 11) or treated ipsilateral lobe (n = 1). Complete continence (no pads) and potency sufficient for intercourse were documented in 100% and 86% of patients, respectively. Matched-pair comparison of focal cryotherapy and RP revealed similar oncologic outcome, defined as needing salvage treatment.

Conclusions

Primary focal cryoablation for low-intermediate risk unilateral cancer affords encouraging oncologic and functional outcomes over a median 3.7-yr follow-up. Close surveillance with follow-up whole-gland biopsies is mandatory.     

Association between preoperative allograft function (effective renal plasma flow) and the change in glomerular filtration rate among living-donor kidney transplant recipients

Background

Predonation kidney function may be an important factor affecting graft outcome. Increased baseline allograft function may be more effective than strategies to slow the decline in glomerular filtration rate (GFR). However, the role of donor effective renal plasma flow (ERPF) on long-term outcome is less well understood. The purpose of this study was to examine the relationship between preoperative allograft function as measured by ERPF and the decline of allograft function as defined by the annualized change in GFR among living-donor kidney transplant recipients.

Methods

We performed a retrospective analysis of 83 patients who underwent living donor renal transplantation at our institution from March 2001 to October 2010. A time series analysis of autoregressive integrated moving average (ARIMA) model was applied to determine the annualized change in GFR after transplantation. Univariate and stepwise multivariate analyses were performed using linear regression between preoperative ERPF and annualized change in GFR after transplantation. We also investigated the influence on annualized change in GFR of other donor or recipient variables.

Results

The ARIMA model revealed that the annualized change in GFR was −1.344 ± 12.476 mL/min/1.73 m² per year. Pearson correlation coefficient for the association between predonation ERPF of the transplanted kidney and the annualized change in GFR was 0.033 (P = .777).

Conclusions

Poor predonation kidney function was not associated with an increased rate of decline of allograft function. Neither donor age nor renal function (preoperative ERPF value) was a valid predictor of change in GFR among living-donor kidney transplant recipients.     

Imaging evaluation of kidney using multidetector computerized tomography in living-related renal transplantation

Background

Multidetector computerized tomography (MDCT) is lesser invasive than conventional angiography and has the advantage of assessment of vessels and surrounding anatomic variants before laparoscopic nephrectomy.

Methods

From May 2005 to March 2011, 62 consecutive living kidney donors of mean age 45.3 ± 12.7 years (range 24-70 y, male:female 26:36) underwent laparoscopic nephrectomy to paired recipients of mean age 44.8 ± 14.0 years (range 17-74 y, male:female 38:24). The clinical characteristics and laboratory data of donors and recipients were collected for analysis. Graft function as indicated by estimated glomerular filtration rate (eGFR) was obtained from the last stable visit of the donors and the best value displayed by the recipients.

Results

There was no significant correlation between CT kidney volume and and eGFR. By univariate analysis, donor age was associated with worse graft function (−0.51 mL/min lower eGFR per 1 year of donor age; P < .0001). Female sex and higher effective renal plasma flow/body mass index ratio were associated with better graft function; conversely, body weight and BMI were associated with poor graft function upon univariate and multivariate analysis. An ERPF of <220 mL/min and a donor age >45 y showed significantly lower eGFR. There was no effect of CT kidney volume <100 mL.

Conclusions

Our preliminary data suggest that CT kidney volume does not predict posttransplantation graft function, but MDCT is still important for analysis of anatomy before laparoscopic nephrectomy among living donors.